The goal of the proposed research is to investigate fever in various malignant diseases by studying the relationship of aspects of the malignant process to production of fever in the host. Specific areas to be investigated include: 1) Investigation of the mechanism of fever in malignant lymphoma and other tumors by study of blood, lymphoid and tumor cells from patients with these diseases; 2) Study of the role of host immune responses in the process of pyrogen production by malignant tissues; 3) Investigation of the process of pyrogen production by mononuclear, malignant or transformed cells in tissue culture, and its relation to other metabolic and morphologic characteristics of these cells. BIBLIOGRAPHIC REFERENCES: Bodel, P. Studies on the mechanism of endogenous pyrogen production. III. Human blood monocytes. J. Exp. Med. 140: 954, 1974. Haeseler, E. and P. Bodel. Role of Kupffer cells in experimental staphylococcal fever. Clin. Res. (abstr) April 1975.